Her mother's boyfriend is watching Wood, then 3 years old, and her 21-month-old brother.

Sipping a fruity drink from a Dixie cup, she watches TV as the man takes the toddler for a bath.

A bloodcurdling scream draws her to the bathroom.

Her brother is sitting on the sink, his face purple as he cries out for help.

Strangers flood into the family's Eastside apartment.

Her baby brother, William Thomas "Billy" Wood, is dead.

Wood was an eyewitness to murder, but no one ever asked her what she saw that morning in January 1977 - and Billy's death was written off as an accident.

"There isn't a day that goes by that memories of 1977 haven't crept in to my daydreams or my thoughts," said Wood, now 40 and living in Chicago.

"There isn't a day that I don't see my brother screaming. And, sometimes, I see him reaching out to me."

Wood was left to live with those memories, first as a scared and confused child, and later as a woman struggling to find her identity and an inner peace.

The unanswered questions and unresolved guilt saddled her with night terrors and paranoia. Wood's relationship with her mother deteriorated. Trust issues made it difficult to sustain normal relationships. At times, she was too emotionally paralyzed to leave her home. She contemplated suicide and determined she could never bring a fragile child into such a brutal world.

But she never forgot. And she remained determined - some way, somehow, sometime - to get justice for her little brother.

While the memories of what happened to Billy will never go away, Wood said she turned a corner in her life Friday as she watched a judge sentence Michael Vincent Ackerman to life in prison for killing her brother.

It was a moment, Wood admitted, that she never thought would come.

And it would not have been possible if not for an open-minded and determined cold case detective - and those terrible childhood memories that Wood just couldn't push out of her head.

Case reopened

Ackerman, 58, was arrested and convicted after Indianapolis police reopened the investigation into Billy's death in response to a call Wood made to Indianapolis police on Feb. 5, 2013.

"For me to open the door to the future, I knew I had to close the door to the past," she explained. "I decided I was going to do something about it. I was going to get someone to listen to me and, if they told me I was wrong, I would be willing to accept that."

Wood found a willing ear and open mind in Sgt. David Ellison, a detective with the Indianapolis Metropolitan Police Department's Cold Case Unit.

She once had a baby brother, Wood told Ellison, and was in the apartment when her mother's boyfriend killed him.

A decade earlier, Wood said she had reached out to police, but was told they did not have the resources to look into the old case.

But Ellison said Wood was believable, despite basing her report on the decades-old memories of a young child.

"I could hear," he recalled, "the pain in her voice."

After the veteran detective reviewed the few case files he was able to find, he decided to re-open the probe. Ellison tracked retired medics and police officers and sought out three medical examiners to review Billy's autopsy.

The detective also conducted formal interviews of Wood - and her mother Debra Shay - as he began to build a case against Ackerman.

On April 24, 2013, what once seemed impossible to Wood became a reality.

Prosecutors charged Ackerman with murder.

Only the beginning

In some ways, the arrest of Ackerman was only the start.

Like all criminal defendants, he was presumed innocent. The prosecutor, with only limited evidence, would have to convince a judge or jury that Ackerman was, beyond a reasonable doubt, responsible for killing Billy.

A trial also meant Wood would have to testify - to recount the memories that had haunted her and, very possibly, face harsh and personal attacks from Ackerman's lawyers.

"I just tried to tell the truth," Wood said of her day on the witness stand. "All I could say is, 'This is what I remember. If it's not enough, I'm sorry.'"

Wood's nervous, sometimes tearful, account was bolstered by the testimony of medical examiners. They said it should have been clear from the autopsy in 1977 that Billy was a victim of fatal physical abuse. Pathologists who reviewed the autopsy report determined Billy had died of injuries to his head and abdomen consistent with blows from a fist. The injuries, they said, were too severe to be accidental - a finding the coroner at the time overlooked when he left the manner of death undetermined.

Ellison also found a picture from the scene - a photograph Wood had never seen and did not know about until after she testified. It showed the Dixie cup she remembered drinking juice from that morning. It was a small piece of seemingly inconsequential evidence, but it verified Wood's vivid childhood memory.

Marion Superior Court Judge Lisa Borges said before pronouncing Ackerman guilty that the limited direct evidence which remained nearly four decades after the killing and the circumstantial evidence pulled together by Ellison sealed the conviction.

"There was only one adult in that apartment when Billy sustained the fatal injuries," the judge explained. "There was only one person who had the ability to deliver that kind of injury."

Still, chief deputy prosecutor Denise Robinson said, the case ultimately hinged on Wood. The coroner at the time, she explained, had left the case open. Because it was never ruled a homicide, the prosecutor explained, no criminal case was initiated.

"Without her contacting detective Ellison," Robinson said, "this case would never have been brought."

Little comfort

However, Ackerman's conviction in June did not bring the peace that Wood so desperately wanted.

"You think that, somehow, if you can just get justice, you'll be whole again," she explained, "But it doesn't work like that. I realized it was going to take time and I threw myself into my work and friendships."

Wood also knew she would have to return to the courtroom to face the man she watched kill her brother. That watershed moment came Friday morning.

And this time, Ackerman looked less defiant and more reserved than he was at his trial, when he glared at every witness called to testify against him. But he still maintained his innocence and said he plans to appeal the conviction.

Dressed in an orange jail uniform, with his hands and feet shackled together, Ackerman slowly rocked back and forth as Wood and several family members took turns telling Borges how Billy's murder had devastated their lives. They all asked the judge to send Ackerman to prison for life.

Wood said she still has many unresolved questions as Ackerman heads to prison. Why didn't anyone ask her what she saw that day? Why did her mother refuse to talk about Billy's death? Why wasn't Ackerman charged at the time? What harm might he have done to others in the decades after he killed Billy? Why didn't police reopen the case when she first approached them 10 years earlier?

But during a visit Thursday to Billy's grave in Franklin, Wood said she's not sure how much more she wants to - or can - continue to push.

"I don't know," she said, "what I would get out of going after the people who let us down."

Instead of looking back, Wood said Friday she is determined to look forward. That means continuing to try to heal herself and advocating for more help for the IMPD cold case "team," of which Ellison is now the only full-time detective.

"I am so fortunate that David Ellison took the time to listen to me and to look into the death of my baby brother," she said. "Without his dedicated effort, this day would not have come."